Raven has much to crow about

DURING the fine weather in September I spent much time outdoors, working in the garden and in my small wood.

Several times the work was stopped by a deep, sonorous bird call. I looked up and spotted great black birds, with bluntly pointed tails, flying.

I’ll always stop work to watch a raven. When I first became interested in birds, 50 years ago, ravens were rare in Ireland. You had to search deep in craggy mountains or along sea cliffs. They had been persecuted by farmers and gamekeepers and, because they have a strong taste for carrion, they were vulnerable to baits laced with strychnine.

Strychnine was banned and attitudes became more enlightened. The birds posed no threat and did a useful job cleaning up road kills and dead lambs in the mountains. Raven numbers increased.

They mate for life and, once mated, they are territorial. With the increase in numbers; there wasn’t room in the mountains and sea cliffs, so they adapted to new habitats. I live in a flat part of the Midlands. Apart from the occasional limestone quarry, we have no traditional raven nest sites. The local birds nest in tall trees.

They are the monarchs of the crow family and our largest passerine, or perching bird. The average weight of an adult male is 1.2 kilos and they have been recorded up to 2 kilos. They are also extremely long-lived. Some of the famous colony in the Tower of London have lived for more than 40 years, though these birds are half-tame and well-minded, due to the superstition that they protect England from foreign invasion. Life expectancy in the wild is less than 20 years.

The intelligence of crows is a fascinating recent discovery. The raven is the largest crow, with the largest brain, so it’s reasonable to expect it to be more intelligent. There is some evidence to back this up.

One of the gauges of animal intelligence is playfulness. Ravens, particularly young ones, are very playful. They play in the air, performing spectacular aerobatics; they’ve been observed sliding down banks of snow for fun and they make toys out of twigs and other objects.

After one experiment involving five tame ravens, I was impressed with their problem-solving abilities. Each bird’s perch had a piece of meat on a string tied to it. The only way it could reach it was by pulling in a length of the string with its beak, standing on the loop and pulling in another length. Shortly, not by trial and error, four of the five birds solved the problem.

Nature Table

Over the next few weeks winter migrant birds will start arriving in Ireland. The fieldfare is a winter migrant thrush, intermediate in size between the resident song thrush and the mistle thrush. It can be identified by slate grey patches on the rump and the back of the head and also shows distinctive white patches under the wings when in flight. The exact timing of their arrival in Ireland depends on when food resources become depleted in their Scandinavian breeding grounds, but the first birds are normally spotted in early to mid-October with the main migration in November. They normally travel in flocks, sometimes mixed with redwings, another migrant thrush. In winter fieldfares mainly eat berries and larger fruit, such as crab apples. If they discover a tree with a heavy crop they will defend it against all comers. They are largely a bird of farmland with mature hedges but are often tempted into gardens in rural and suburban areas by heavy berry crops, including cotoneaster.

— Dick Warner